1. Field of the Invention
The present invention relates to destruct initiation circuits, and more particularly to a destruct initiation circuit which includes a high current source connected to a detonator by a gap switch.
2. Description of the Prior Art
Prior destruct initiation circuits which used gap switches, such as that disclosed in U.S. Pat. No. 3,628,458 by Emmett J. Sands, provided a single circuit for both auto-destruct and command destruct signals. These circuits had several problems which could cause premature triggering of the gap switch, or could cause no triggering of the gap switch. For example, the use of one SCR for the auto-destruct signal and a second SCR for the command destruct signal to switch a high current pulse through a trigger transformer to trigger the gap switch results in multiple triggers being applied to the gap switch, the so-called "rapid fire" problem, due to voltage gradients in the circuit. Also, failure of a diode in the high voltage bridge rectifier circuit causes a high voltage ac signal to be impressed across the energy-storage capacitor resulting in failure due to overheating of the capacitor or premature firing of the gap switch due to the abnormally high voltage peaks. Additionally, prior circuits were susceptible to noise induced signals triggering the gap switch.
Another problem was the inability to isolate faults in the system since the telemetry signal was either saturated by the high current output pulse, or the almost instantaneous response of the circuit resulted in no telemetry data of the circuit status.